1. Field of the Invention
This invention relates generally to network management and more particularly to network monitoring applications.
2. Description of the Related Art
The global computer network, known in one form as the “Internet,” has become an important instrument for commerce, entertainment, communication, and information retrieval. Network-enabled intranet applications and powerful desktop computers have resulted in a significant increase in network traffic. The increase in network traffic has resulted in increases in demand for network bandwidth, performance, and predictable quality of service as well as multimedia and security oriented network services.
To support the increasing growth in network traffic, managing communications equipment has become increasingly important. Network management applications, such as NetFlow services and applications from Cisco Systems, Inc. of San Jose, Calif., provide measurement technology by efficiently providing the information required to record network and application resource utilization. Network management includes network traffic accounting, usage-based network billing, network planning, network monitoring, outbound marketing and data mining capabilities for both service provider and enterprise customers. The International Organization for Standardization (ISO) has partitioned network management activities into five major areas (also known as FCAPS, for the initials of each functional area): fault management, configuration management, accounting management, performance management, and security management.
These network management activities require the collection of data from communications equipment or network nodes. The Internet consists of a large installed base of many types of switches, routers, and other communications equipment and software employing multiple communications protocols. Among these protocols is the well-known Internet Protocol (IP), which is a connectionless communications protocol that provides, among other things, transport services for packetized data. Collecting network data typically requires, for example, that every IP packet (also referred to as “IP datagram”) being forwarded by a router or other communications equipment must also be processed by the communications equipment's one or more processing engines. Thus, enabling network monitoring often reduces the throughput of the communications equipment, for example, reducing the number of IP packets being forwarded because processing every IP packet with the one or more processing engines to collect network data adds significant overhead to the functions the processing engine(s) must perform causing the processing engine(s) to become a bottleneck. The additional overhead on the processing engine(s) often significantly reduces the forwarding rate of the communications equipment and occasionally causes equipment failure.
To prevent equipment malfunctions and reduced throughput, collecting the network data from communications equipment must often be discontinued, preventing the collection of valuable network management data. A method of collecting data is needed that does not reduce network operations or cause equipment malfunctions. In addition, a method is needed that is compatible with the installed network infrastructure.